29.5.2023

Kemijoki – Major construction project for pumped storage hydropower plants that enable safe energy transition

We are advising Kemijoki Oy as the company is exploring the possibility of building pumped storage hydropower plants as part of its existing production infrastructure in Northern Finland.

The socially significant project enables safe energy transition and would have a significant role in mitigating climate change.

The 200–600 MW pumped storage power plants explored by Kemijoki Oy would increase the regulating capacity of hydropower in Finland by up to 4,000 MW. The increase is exceptionally significant since Finland’s current hydropower capacity, which is mainly regulatable, is 3,100 MW. The scale of the project is also reflected in the fact that the nominal capacity of the company’s largest operating hydropower plant, Petäjäskoski hydropower plant, is 182 MW. The scale of the possible investment totals up to 3 billion euros.

The production of weather-dependent wind and solar power will increase significantly in Finland. This requires ensuring sufficient production capacity that can be regulated, and hydropower is the most important form of such production.

The overall generating capacity of pumped storage hydropower is on the rise in Europe and elsewhere in the world, reducing the need of fossil fuels. The pumped storage plant consists of two reservoirs that will help the plant to produce power when demand is high by running water through turbines down from the upper reservoir to the lower reservoir. When demand for electricity is low, the pumped storage plant will pump water back up into the upper reservoir.

Latest references

We are assisting Verne Global Ltd, the leading provider of sustainably powered HPC data centers in the Nordics, in developing a data center in Mäntsälä, Finland. We advised Verne in acquiring the real estate company managing the Mäntsälä site, as well as in the subsequent acquisition of the site itself. Our assistance extends beyond real estate transactions to include permitting and tax-related matters. Additionally, we advise Verne on grid connection and electricity supply matters. The acquisition of the project site in Mäntsälä marks Verne’s fourth data center in Finland, reinforcing its position as a leader in sustainable and scalable data center solutions. The Mäntsälä campus, spanning 10 hectares and located just a 40-minute drive from Helsinki-Vantaa International Airport, will initially offer a capacity of 70 MW. The facility is designed to support data-intensive enterprises and AI innovators running HPC, machine learning, and other high-intensity workloads, all while operating exclusively on renewable energy. Verne’s new facility will adhere to the company’s best practice design principles, focusing on maximizing efficiency and minimizing environmental impact. The campus will be powered entirely by renewable energy sources, and waste heat generated by the data center will be utilized for local community heating projects. The company is working closely with the Mäntsälä Municipality to ensure the new facility benefits the local area, including plans to harness waste heat for district heating. Construction of Verne’s Mäntsälä data center is set to begin in mid-2025 and is expected to take two years to complete. This expansion is a strategic move in Verne’s long-term plan to build out its sustainably powered data center platform, which was acquired by Ardian, a world-leading private investment house, in early 2024. Ardian has already invested over EUR 1.6 billion in the Nordics, focusing on energy transition and digital infrastructure projects, and is working with Verne to drive sustainable growth across the region.  Read Verne Global’s press release.
Case published 20.2.2025
We are assisting Verne Global Ltd, the leading provider of sustainably powered HPC data centers in the Nordics, in expanding a data center in Helsinki region, Finland. In the autumn of 2024, we acted as Verne’s advisor in acquiring the land at its existing Helsinki data center campus, securing room for future expansion. In addition to real estate development, our advice covers permitting and construction related legal matters. The expansion marks another milestone in Verne’s ambitious growth strategy for the Nordics, following the recent announcement of its new facility to be built in Mäntsälä, Finland. The land was acquired from Onvest, a family-owned company with a long history in the region. The site’s strategic location provides excellent connectivity to power and fibre networks, proximity to Helsinki Airport, and easy access to the city centre – making it ideal for organisations across industries looking for reliable, accessible, and well-connected facilities. Verne plans to develop the site further, leveraging its 70MW capacity to meet the increasing demand for sustainable, high-performance compute infrastructure. Designed with high-density compute in mind, the planned expansion will include two new buildings fully equipped to meet the technical requirements of AI, HPC, and other intensive workloads. Verne remains committed to sustainability, with the Helsinki campus running on 100% renewable energy. Waste heat generated by the data center is repurposed through a direct connection to the local district heating network. All new facilities will be built to support liquid cooling, enabling efficient management of the high heat levels generated by AI and other intensive compute workloads. Additionally, Verne uses renewable diesel for its backup power generators in Finland, reducing greenhouse gas emissions from the generators by an average of 90%. News: Verne expands Helsinki data center campus with strategic site acquisition. Read Verne Global’s press release.
Case published 20.2.2025
Castrén & Snellman is acting as the legal advisor to the City of Pori and Pori Energia Oy in the finance arrangement whereby debt facilities in the total amount of EUR 292 million are secured for the purpose of refinancing the existing liabilities and fuelling the future growth of Pori Energia. Pori Energia and its financiers signed a Finnish law governed facilities agreement for this purpose on 13 January 2025. Pori Energia, a multi-utility company, operates in various sectors including district heating, electricity distribution, and electricity generation through CHP and renewable sources. The company also provides wind power services and industrial energy solutions in the Satakunta region where it has c. 60,000 customers.
Case published 6.2.2025
Castrén & Snellman is acting as the legal advisor to the City of Pori in its sale of a 49% stake in Pori Energia to Polhem Infra. Pori Energia, a multi-utility company, operates in various sectors including district heating, electricity distribution, and electricity generation through CHP and renewable sources. The company also provides wind power services and industrial energy solutions in the Satakunta region. This strategic partnership between the City of Pori and Polhem Infra aims to enhance Pori Energia’s financial stability and investment capabilities, enabling the company to further its efforts in the energy transition and continue delivering high-quality energy services to its customers. Polhem Infra, owned by Swedish state pension funds, focuses on investments in critical infrastructure, including renewable electricity generation, energy storage, energy distribution, digital infrastructure, and transport infrastructure. The transaction values Pori Energia at EUR 905 million. 
Case published 31.1.2025